1. Technical Field
Various embodiments of the present disclosure relate to methods of fabricating semiconductor devices and, more particularly, to methods of forming patterns having different shapes.
2. Related Art
In the fabrication of semiconductor devices, a lot of effort has been focused on integrating more patterns in a limited semiconductor substrate area. That is, attempts to increase the integration density of the semiconductor devices have typically resulted in formation of finer patterns. Various techniques have been proposed to form fine patterns, such as small contact holes having nano-scale critical dimensions (CD).
The patterns in semiconductor devices are formed using a photolithography process. However, due to image resolution limits in the photolithography process, there are limitations on how small patterns may be formed. Methods of forming fine patterns using self-assembling polymer molecules is a candidate for overcoming the image resolution limits, which are due to the nature of optical systems used in the photolithography process and the wavelengths of light generated from light sources of the optical systems. However, there may still be limitations in simultaneously forming fine patterns having different shapes on a substrate using directed self-assembly of polymer molecules. Accordingly, various techniques have been developed to overcome these difficulties.